Does it make sense?

There is nothing wrong with the way this chart is constructed. I'd probably have the labels all set to the right in a column but otherwise, no real issues.

However, this chart bugs me in another way. I just cannot make sense of it. The year 1999 appears to be some kind of watershed year for these 4 automakers: they roughly split the market that year. It is very strange that all the lines would meet at a point and then spread out again. It seems very unnatural. It makes me wonder if we are looking at bad data. Anyone have access to the underlying data or knowledge of what kind of watershed was 1999?

Reference: "An Ambitious Lexus Takes On the Europeans", New York Times, April 15 2006.

Comments

Hi -

Can't make sense of the numbers in that form either: what it looks like is rather they took indexed numbers 1999 = 100 and then looked to see how many vehicles someone sold in that year to get at the vehicle levels.

Otherwise, it makes little sense...

John

PS: And the chart would have been much, much better if they had indexed the first year as being equal to 100: then the relative growth would be instantly clear...

The only way they would all converge would be if the chart were indexed to 1999, as a previous poster mentioned. That would mean that the purpose of the chart was to track how manufacturers have fared since (or before) 1999 by starting them all at zero, like a race. But this chart is clearly not showing a comparison - those are actual vehicles sold.

Adding to the puzzle is that the Mercedes line seems to cross just ahead of everyone else.

No "event" could explain a covergence like that (except maybe a law being passed that year that mandated the production of 175,000 cars). Either it just happened, or the chart is in error.

I think what happened is they flip-flopped back and forth between two graphs - market share (indexed to 100 in 1999) and vehicles sold, and the graph that got published contains the lines from market share and the axes from vehicles sold. It's meaningless.

Same 2005 number for Lexus quoted here:
http://www.autoweek.com/apps/pbcs.dll/article?AID=/20060418/FREE/60417006/1041
plus the additional statement:
"the sixth straight year it has been the best-selling luxury brand in the United States."
which matches the chart.